Steel Structure Workshop Construction – What is the Hole-Making Process in Steel Structure Processing?
# English Translation During the fabrication and welding of steel structures, welding shrinkage and deformation are unavoidable. Therefore, determining the proper timing for hole making during production will significantly affect the precision of the finished product. How much do you know about the **hole-making process in steel structure fabrication**? Please refer to the analysis below. The dimensional accuracy of hole groups at the on-site connection points of columns and beams directly affects the installation accuracy of steel structures. It is crucial to choose the right time for drilling. 1. Drill holes at one end of the member first. After assembly, welding and deformation correction are completed, drill holes at the other end. 2. Mark the hole positions on the member during steel structure fabrication in Huai’an in advance. After assembly, welding and deformation correction are finished, re-mark and confirm the positions before drilling. 3. After the member is welded and deformation-corrected, finish the end face. Then take the finished surface as the datum for marking and drilling. 4. Take welding shrinkage, deformation allowance and allowable tolerance into account during marking, and drill directly. Mechanical hole-making equipment includes electric drills, pneumatic drills, vertical drilling machines, radial drilling machines, gantry radial drilling machines, multi-spindle drilling machines and NC drilling machines. For gas hole-making, a simple method is to install a basic auxiliary device on the gas cutting nozzle, which can drill holes up to **φ30**. Hole making using drilling jigs and stacked plate drilling is a method not yet widely used in China. Members are fixed with clamps, and drill bushes are made of carbon steel or alloy steel. The two planes of the drilling jig plate shall be parallel with a deviation not exceeding **0.2 mm**. The axis of the drill bush shall be perpendicular to the plane of the drilling jig plate with a deviation not exceeding **0.15 mm**. The allowable manufacturing tolerance of the integral drilling jig complies with relevant standards. Through the above analysis, you now understand the hole-making process in steel structure fabrication. To achieve high-quality steel structure fabrication, the hole-making process must be strictly controlled.